I'm curious, is it really that hard to identify competent programmers? Surely asking a few technical questions that include some element of programming should be enough. I feel like there's about 5-10 articles on this subject every week, all of which say or or less the same thing. In very nearly every case that I've interviewed someone, I've been able to easily decide if they were a hire or a no hire about 20 minutes into the interview process. I'm sure for certain positions or certain companies who are solving difficult problems, things could be more complicated, but the vast majority of us just aren't in that situation.
It seems like the rather more difficult problem is getting competent programmers to want to work at your company and apply.
Identifying competent programmers is hard as long as you try to quantify it. You don't make decisions based on rational facts that come from a rational process, as nobody does. In the end, the decision comes from a feeling that we so hard try to belittle.
The rational mind can make a "decision", like "this candidate passed all our interviews and qualifies on paper: that means we can hire him". But the true decision of hiring someone is more like a "to engage or not to engage ourselves with this guy, in a joint (work) life together and into the future". Conversely, you can just decide to nominally hire people but never back it up on a personal, human level.
The process of hiring is golden as a negative filter: you want to weed out people who factually aren't up to it. But there's no positive filter that you can unilaterally apply. In the end, you just have to let yourself "know" who to hire because there's nothing else you can do.
Part of the problem, and the reason we have posts about hiring constantly, is that there's no solution to the problem. Every team is composed of different types and amounts of people, every company is different, everybody has had success or failure with different techniques, every recruiter brings different types of people, etc. There are a lot of people you can flip the bozo bit on quickly but others who are just bad interviewers and you have to draw out a bit more. There's people who just rub me the wrong way so I'm harsher than others sitting in the same room at the same time. And once you get past "These 5 people are competent but which one would I like to spend my week with?" the complexity goes up tremendously. If you're hiring the person who will sit behind you 8 hours a day it's a different deal than getting the 50th programmer in your department.
It seems like the rather more difficult problem is getting competent programmers to want to work at your company and apply.